Set-Based Design Method for the Early Phase Design of Structures With Uncertainties

2010 ◽  
Author(s):  
Masato Inoue ◽  
Yutaka Hattori ◽  
Haruo Ishikawa
Keyword(s):  
Structural Design ◽  
Early Phase ◽  
Design Method ◽  
Analysis Tool ◽  
Design Variables ◽  
Point Solution ◽  
Design Solutions ◽  
Set Based Design ◽  
Express Information ◽  
Analyze Structure

Since an early phase of design intrinsically contains uncertainties from various sources of variations, design performances are fluctuating or reflect uncertainty caused by uncertain design variables. Analysis tool such as finite element method (FEM) is useful for structural analysis. However, using unique point solution does not express information about uncertainties. Designers need to figure out an outline of the structural feature and have to obtain a design idea under some uncertain design information in a structural design at the early phase of design. We have proposed a preference set-based design (PSD) method that generates a ranged set of design solutions that satisfy sets of performance requirements. This study proposes a structural design method for the early phase of design based on the PSD method that is possible to analyze structure with design uncertainty by elastic FEM and obtain a ranged set of design solutions. That is, a design method for analyzing structures and obtaining a ranged set of design solutions with uncertainties of material property and dimension of structure (coordinates of geometry) under fluctuating distribution of performance characteristics of stress and displacement is proposed. In order to illustrate the availability of our approach, design problem of 3-dimensional truss structure is solved.

Strength Model Uncertainties of Burst, Yielding, and Excessive Bending of Piping

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Kleio Avrithi ◽  
Bilal M. Ayyub
Keyword(s):  
Structural Design ◽  
Design Method ◽  
Strength Model ◽  
Allowable Stress ◽  
Model Uncertainties ◽  
Reliability Based Design ◽  
Design Variables ◽  
Strength Models ◽  
Potential Use ◽  
Allowable Stress Design

Nuclear safety-piping is designed according to the ASME Boiler and Pressure Vessel Code, Sections III, NB-, NC-, and ND-3600 that use the allowable stress design method (ASD). The potential use instead of reliability-based design equations for nuclear piping could benefit the structural design by providing, among others, consistent reliability levels for piping. For the development of such equations, not only the probabilistic characteristics of the design variables are needed, but also the quantification of the uncertainties introduced by the strength models that are used in order to estimate the resistance of pipes subjected to different loadings. This paper evaluates strength models, and therefore provides necessary information for the reliability-based design of pipes for burst or yielding due to internal pressure and for excessive bending.

Design Optimization for a Parallel MEMS Mechanism With Flexure Joints

2004 ◽  
Author(s):  
Byoung Hun Kang ◽  
John T. Wen ◽  
Nicholas G. Dagalakis ◽  
Jason J. Gorman
Keyword(s):  
Performance Metrics ◽  
Design Method ◽  
Design Tool ◽  
Analysis Tool ◽  
Parallel Mechanisms ◽  
Analysis And Design ◽  
Design Variables ◽  
Stiffness Matrices ◽  
Flexure Joints ◽  
Task Specification

This paper presents an analysis tool and design method for MEMS parallel mechanisms. Due to processing constraints in MEMS fabrication, flexure joints are frequently used in MEMS mechanisms. Flexure joints offer advantages over other joint designs due to their monolithic characteristics. They can be used to reduce the size of manipulators or to increase the precision of motion. Their inherent flexibility, however, also results in task space compliance which needs to be carefully designed to match the task specification. This paper presents an analysis and design tool for such mechanisms by using the differential kinematics. Performance metrics are chosen based on manipulability and task stiffness matrices, which in turn are used in a multi-objective optimization. As an illustrative example, a 1-DOF MEMS parallel mechanism based on the macro- and meso-scale models designed by NIST is considered with several choices of performance metrics and design variables. The resulting designs are successfully fabricated using DRIE process.

Optimum Structural Design of Naval Vessels

2003 ◽  
Vol 40 (03) ◽  
pp. 149-157
Author(s):  
Seo Seung II ◽  
Son Keon Ho ◽  
Park Myung Kyu
Keyword(s):  
Structural Analysis ◽  
Structural Design ◽  
Design Method ◽  
Design Standards ◽  
Naval Vessel ◽  
Main Design ◽  
Optimum Structural Design ◽  
Design Variables ◽  
Analysis Theory ◽  
The U.S

Naval vessels are not regulated by class rules, but by special regulations. This study introduces the concept and characteristics of the regulations of the U.S. Navy, which has been the most reliable in setting design standards of naval vessels and helps designers comprehend the effect of each regulation on design results. Also, an optimum structural design method combined with structural analysis theory is proposed for an actual naval vessel to be designed according to U.S. Navy regulations. The validity of the proposed method is shown by the optimum design results for the midship section. The optimum spacings of longitudinal and transverse web frames are found, and the effect of the main design variables is investigated.

Optimal Structural Frequency Design of Stiffened Shell

2012 ◽  
Vol 157-158 ◽  
pp. 1636-1639 ◽  
Author(s):  
Da Hai Mi ◽  
Rui Yang ◽  
Liang Zhou ◽  
Yang Liu ◽  
Dong Ming Guo
Keyword(s):  
Structural Design ◽  
Design Method ◽  
Frame Structure ◽  
Size Optimization ◽  
Optimum Structure ◽  
Regular Grid ◽  
Stiffened Shell ◽  
Evolutionary Structural Optimization ◽  
Design Variables ◽  
Test Models

Frequency-aimed optimal structural design of stiffened shell is concerned. It is a reverse design problem for the first several modal frequencies to converge to a set of target value. A design method combined modified bi-directional evolutionary structural optimization (BESO) and size optimization is presented. Optimization model consists of skin and regular grid frame structure. To solve irregular branches and holes that often exist in ordinary topology optimization results, instead of elements, the existence states of ribs in the frame are used as design variables and sensitivity of the rib is discussed. Detailed design is conducted by size optimization. Example shows that frequency requirements are achieved. And the optimum structure is regular and clear, the localized modes problem is avoid. This is very suitable for designing airplane wind tunnel flutter test models.

Simulation of Developmental Process of Organism and Application to Structural Design

2005 ◽  
Vol 9 (2) ◽  
pp. 142-149 ◽  
Author(s):  
Masato Inoue ◽  
◽  
Yoshiyuki Matsuoka
Keyword(s):  
Structural Design ◽  
Developmental Process ◽  
Design Method ◽  
Design System ◽  
Generation System ◽  
Improve Design ◽  
Form Generation ◽  
Ancient Times ◽  
Design Solutions ◽  
Design Ideas

In the early processes of design called conceptual and preliminary design, diverse design ideas must be obtained under the constraint of unclear design conditions. Since ancient times, designers have been referred to form and structure of natural organism to create new artifacts. Design method referencing organisms could develop new designs and improve design capabilities. This paper describes a design system referencing emergent organism evolution, diversity, and environmental adaptation to obtain diverse design solutions. We simulate developmental process of organism, "induction" and "apical dominance" for diverse organism morphogenesis and propose form-generation system for obtaining diverse design solutions in a self-organizing manner using cellular automata. Generated organisms are adapted to the environment. We add a process in which forms are structurally adapted, optimizing diverse design ideas. To verify effectiveness proposal, we apply our proposal to the structural design of chairs. We discuss the effectiveness of our proposal applying organism morphogenesis for obtaining diverse design solutions.

Upgradable Design for Sustainable Manufacturer Performance and Profitability and Reduction of Environmental Load

2016 ◽  
Vol 10 (5) ◽  
pp. 690-698 ◽  
Author(s):  
Shuho Yamada ◽  
◽  
Tetsuo Yamada ◽  
Stefan Bracke ◽  
Masato Inoue ◽  
...  
Keyword(s):  
Product Design ◽  
Design Method ◽  
Design Methods ◽  
Laser Printer ◽  
Functional Requirements ◽  
Product Price ◽  
Environmentally Conscious ◽  
Design Solutions ◽  
Set Based Design ◽  
Sales Strategies

This study proposes an upgradable product design method that falls under the category of “environmentally conscious” product design methods. The method enhances the product’s performance by exchanging or adding only a few of its components. In addition, the proposed method reduces the usage as well as wastage of resources by preventing the disposal of the product itself. This study primarily focuses on manufacturer profit, which was presented as an ill-argued topic in a previous study on upgradable product design methods that potentially provide enhanced sales strategies for upgradable products with an underlying consideration of company sustainability. Moreover, the proposed method in this study assesses how design information uncertainties associated with future prediction (as a ranged value) apply to the concept of set-based design to ultimately obtain ranged sets of design solutions and sales strategies that satisfactorily meet profit, environmental, and functional requirements. Finally, the proposed method obtains ranged design solutions that can realize low environmental loads, low product price, and a highly profitable upgradable product via exclusive application to a multifunctional laser printer scenario. The results of this study indicate the effectiveness of such an upgradable product design method as a vital approach in building a sustainable society.

Set-Based FEM for Product Design With Uncertainties

2009 ◽  
Author(s):  
Haruo Ishikawa ◽  
Masato Inoue
Keyword(s):  
Product Design ◽  
Structural Property ◽  
Concurrent Engineering ◽  
Early Phase ◽  
Fem Analysis ◽  
Truss Structure ◽  
Analysis Tool ◽  
Analyze Structure

Analysis tool such as FEM which can analyze structure with design uncertainty is needed for considering the structural property of the products from the early phase of design dealing with various uncertainties. This paper describes the application of the concept of Set-Based Concurrent Engineering (SBCE) to FEM. The methodology of the set-based FEM analysis of 2D truss structure is presented. A prototype program is developed to obtain the interval solutions satisfying the requirements of deformation and rigidity.

scholarly journals Design of Bldc Motor for Agriculture Pump Application

2019 ◽  
Vol 8 (2) ◽  
pp. 441-446
Keyword(s):  
Design Method ◽  
Fem Analysis ◽  
Element Model ◽  
Analytical Models ◽  
Design Parameters ◽  
Analysis Tool ◽  
Bldc Motor ◽  
Analytical Design ◽  
Design Variables ◽  
Design Calculations

This paper presents the analytical design method for surface mounted BLDC motor to meet the performance requirements of submersible Pump for agriculture application. The design calculations involved assumption of various design variables viz. Stacking factor, leakage factor, Flux densities in stator and rotor yokes and flux density in the stator teeth etc. With these assumptions the geometry of the intended motor is derived. The geometrical information like the rotor diameter, rotor and stator thickness and stator teeth thickness etc. obtained from the analytical calculations are used as input to Finite Element Model (FEM) Analysis tool FEMAG. The Torque-Speed characteristics, back EMF, flux densities in various parts of the motor are obtained from FEM Analysis and the same are compared with the results obtained from Analytical design. Various designed parameters like airgap length, stack length and magnet widths are varied and their influence on the characteristics of the intended BLDC motor is obtained through FEM Analysis. Based on the analytical models and FEM Analysis the design parameters are tweaked until the desired performance for the agriculture pump is accomplished.

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